Evaluation of photodynamic therapy on heterotypic biofilm: Candida albicans, Bacillus subtilis and Bacillus atrophaeus

• Grant number: 13/22808-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: February 01, 2014
• End date: January 31, 2015
• Field of knowledge: Biological Sciences - Microbiology - Applied Microbiology
• Principal Investigator: Antonio Olavo Cardoso Jorge
• Grantee: Thais Alves dos Santos
• Host Institution: Instituto de Ciência e Tecnologia (ICT). Universidade Estadual Paulista (UNESP). Campus de São José dos Campos. São José dos Campos , SP, Brazil

Abstract

The increase in the survival and resistance of microorganisms organized in biofilms highlights the need for new therapies to break through this barrier, such as photodynamic therapy (PDT) is an alternative, effective and non-invasive treatment. This research project has to evaluate in vitro the effect of photodynamic therapy on heterotypic biofilm formed by associations of Candida albicans with Bacillus subtilis and Bacillus atrophaeus, using photosensitizer rose bengal (12.5M) and green light emitting diode (LED) in the irradiation time of 3 min. Standard strains of B. subtilis (ATCC 19659), C. albicans (ATCC 18804) and B. atrophaeus (ATCC 9372) will be used. Heterotypic biofilms, obtained by the association of C. albicans and B. subtilis, C. albicans and B. atrophaeus will be formed in 96-well plates for 48 h. The experimental groups of PDT will be formed the following combinations: 100 mL of heterotypic biofilm, 100 mL rose bengal and LED (P+ L+), 100 mL of heterotypic biofilm, 100 mL of 0.9% NaCl and LED (P- L+), 100 mL biofilm heterotypic and 100 mL rose bengal (P+ L-) and 100 mL heterotypic biofilm and 100 mL of 0.9% NaCl (P- L-). Samples will remain in pre-irradiation for 5 min in motion. Serial dilutions will make and aliquots of 100 mL of the dilutions will be plated on Brain-Heart Infusion Agar and incubated at 37 °C for 48 h. After the incubation period, the Colony Forming Units per milliliter (CFU / mL) will be counted and log-transformed. The results will be statistically analyzed by analysis of variance (ANOVA) and Tukey test with a significance level of 5%. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

SILVA, MICHELLE PENELUPPI; DOS SANTOS, THAIS ALVES; DE BARROS, PATRICIA PIMENTEL; RIBEIRO, FELIPE DE CAMARGO; JUNQUEIRA, JULIANA CAMPOS; CARDOSO JORGE, ANTONIO OLAVO. Action of antimicrobial photodynamic therapy on heterotypic biofilm: Candida albicans and Bacillus atrophaeus. Lasers in Medical Science, v. 31, n. 4, p. 605-610, MAY 2016. (13/22808-0)